At present, a majority of smart phones adopt a double CPU (Central Processing Unit, central processing unit) structure for data processing, where one of the CPUs is a baseband CPU, used for executing basic functions such as a wireless protocol, and the other CPU is an application CPU, used for running application programs and interfaces. Because the functions of the two CPUs are different, multiple application programs running on the application CPU need to invoke the functions of the baseband CPU. In the prior art, communication between the double CPUs is generally performed directly through a serial port/high-speed serial port/USB (Universal Serial Bus, universal serial bus) port/shared memory.
The implementation of the communication between the double CPUs directly through the serial port/high-speed serial port/USB port/shared memory merely solves a problem of a basic communication channel. Due to multiple functions of the baseband CPU and multiple applications of the application CPU, in the running process, a great deal of invocation between the baseband CPU and the application CPU is generated. If the application CPU invokes the functions of the baseband CPU only simply through the serial port/high-speed serial port/USB port/shared memory, a smart phone needs to schedule invocation programs between the baseband CPU and the application CPU through complicated synchronization and mutual exclusion; otherwise, plenty of conflicts occur. On the basis of the communication channel of the serial port/high-speed serial port/USB port/shared memory between the baseband CPU and the application CPU, if each invocation program between the application CPU and the baseband CPU adopts an RPC (Remote Procedure Call Protocol, Remote Procedure Call Protocol) mechanism, a process of communication between the double CPUs is complicated.